JP2020033569A - Process for controlling porosity of carbon blacks - Google Patents

Abstract

To provide a carbon black having a reduced porosity and a process for manufacturing the same.SOLUTION: There is provided a furnace black having a statistical thickness surface area of 130 m/g or more and 350 m/g or less, in which the ratio of BET surface area to the statistical thickness surface area (STSA surface area) is less than 1.1 if the STSA surface area is 130 m/g or more and 150 m/g or less; the ratio of BET surface area to the statistical thickness surface area is less than 1.2 if the statistical thickness surface area is more than 150 m/g and 180 m/g or less; the ratio of BET surface area to the statistical thickness surface area is less than 1.3 if the statistical thickness surface area is more than 180 m/g; and the statistical thickness surface area and the BET surface area are measured according to ASTM D 6556.SELECTED DRAWING: None

Description

  The present invention relates to a process for controlling the porosity of carbon black, the carbon black produced thereby and an apparatus for performing the process of the present invention.

Background of the Invention

  "Carbon Black", edited by Jean-Baptiste Donnet et al., Second Edition, Marcel Dekker Inc. According to the general knowledge of those skilled in the art of carbon black, as exemplified on pages 35-39 of New York (1993), carbon black is used in the furnace process for producing carbon black. Can be controlled by the location of the quench in the furnace reactor. The faster the newly formed carbon black is quenched, the lower its porosity. The ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) can be used as a measure of porosity. In the case of carbon black having a fine particle size, this ratio is equal to or slightly less than the unity of non-very short quenched carbon black (no porosity) and is formed within a longer quench time. Greater than the unity of carbon black to be used. Since the quenching means can only be placed at fixed locations along the reactor, very fine particles of carbon black always show a certain amount of porosity. The optimal location is not always available. As a result, the reaction may not end at the exact moment carbon black formation is just completed. Furthermore, different residence times not only affect the porosity, but also the surface chemistry of the carbon black. The surface of very short, quenched carbon black is rich in hydrogen from CH groups or groups similar to the olefinic double bond. These surface chemistries may not be desirable for all applications where carbon black is commonly available.

  For tire applications, carbon black having a high surface area and low porosity can improve the tire's wear resistance. On the other hand, when furnace black is produced with a short quenching period, as described above, in order to achieve a high surface area and low porosity, the resulting surface chemistry, especially olefinic surface groups, is very low. This leads to short vulcanization times and impairs the processability of the rubber compound.

  Therefore, in order to avoid the above-mentioned disadvantages of short quenched carbon black, the carbon black voids in the furnace process independently of the independent of the quenching position. There remains a need for a process for the production of carbon black that can control the rate, and in particular, reduce it. There is also a particular need for carbon blacks that exhibit an improved balance between wear resistance and processability of rubber compounds in tire applications.

According to the present invention, while limiting the amount of CO ₂ fed to the reactor, combined to increase the inert gas concentration in the reactor, in order to obtain less than 1.2 k-factor, in forming a combustion gas (combustion gas) stream, by adjusting the stoichiometry of the combustible material (combustible material) for O _2, in furnace process (furnace process), the porosity of the carbon black easily It can be controlled and, in particular, reduced.

  The prior art has proposed a process for producing carbon black using near stoichiometric combustion.

  U.S. Pat. No. 3,475,125 discloses that at least one high temperature in a reaction zone is produced by burning a first combustible mixture of a hydrocarbon fuel and an oxidant in a combustion zone. A process for producing carbon black is described that results in a combustion gas stream. This first flammable mixture contains substantially the stoichiometric amount of oxidizing agent required for combustion of the fuel. The first combustible mixture is combusted in the presence of steam which is present in an amount sufficient to protect the combustion zone refractory lining from excessive temperatures. Optionally, at least obtained by burning a second combustible mixture of a hydrocarbon fuel and an oxidant comprising an amount of oxidant in an amount greater than the stoichiometric amount required for combustion of said fuel. One other hot combustion gas stream is supplied to the reaction zone. This process is described to increase the yield of carbon black while protecting the furnace refractories from excessive temperatures.

  U.S. Pat. No. 4,294,814 teaches that a vortex of hot combustion gases is introduced into a first stream of hydrocarbon feed by axially introducing a first stream of hydrocarbon feed. By introducing a second stream of hot combustion gases circumferentially or tangentially to form around, and by introducing a third gas stream radially into the reactor to form around it. Discloses a process for producing carbon black having a high structure. According to a preferred embodiment, one of the second and third streams, including the combustion gas, results from a substoichiometric ratio of combustible material to oxygen, while the other combustion gas stream comprises oxygen. On the other hand, resulting from the excess stoichiometry of the combustible material, both combustion gas streams are mixed and overall stoichiometric conditions are achieved at a very high temperature in the center of the reactor, where A first stream of hydrogen feed is provided without contacting the reactor walls. According to the teachings of this prior art document, this results in a carbon black having a very high structure.

  EP-A-982 378 relates to a furnace process for producing carbon black in which the hot combustion gas stream is formed and the oxygen concentration of the combustion gas is at most 3% by volume when the feedstock is introduced. . It is described that the advantage of reducing the oxygen concentration as much as possible is that the aggregate size of the carbon black is small and the aggregate having a large particle size is suppressed. In addition, the process has resulted in carbon blacks having a narrow particle size distribution.

  U.S. Publication No. 2002/0090325 teaches that in the combustion section, complete combustion of the fuel at the highest possible temperature and at an air ratio close to 1 while suppressing damage to the refractory of the reactor wall. The problem of producing carbon black with a small particle size and a narrow aggregate size distribution will be described. Furthermore, in the prior art part of this document, Japanese Patent Application No. 10-38215, which is not related to the production of carbon black, is discussed. This Japanese reference states that at least immediately prior to the combustion reaction, the oxygen concentration can be reduced by using lean air, for example, by recycling exhaust gas or by diluting the air with an inert gas such as nitrogen. A burner combustion method is disclosed where is much lower than normal air. In U.S. Patent Application No. 2002/0090325, this concept has been adopted since the production of carbon black with stable quality can be difficult if such a method is applied to the furnace producing carbon black. Have been considered unsuitable for the production of carbon black. In addition, extra equipment is required to dilute the oxygen concentration. Thus, US Patent Application No. 2002/0090325 states that in the first reaction zone, the air supply port (s) and the fuel supply port (s) are spaced apart and independent of each other, Next, a furnace structure is proposed in which combustion air and fuel are separately injected into the furnace and burned in the furnace. This results in a carbon black with a small particle size and a narrow agglomerate size distribution and minimizes damage to the refractory of the reactor walls in the combustion zone.

  U.S. Pat. No. 7,655,209 discloses that reactor off-gas is used, preferably to generate combustion gases without natural gas or other auxiliary combustible gas feed streams. It relates to a so-called "deep fuel rich" process for producing carbon black using an oxidizing gas stream providing oxygen in an amount of less than 80% of the stoichiometric amount. Preferably, the offgas is preheated, dehydrated and, if necessary, carbon dioxide is removed. Thereby, the contents of hydrogen and carbon monoxide in the reactor off-gas are utilized as combustible materials. The advantage of this method is that the more complete use of the raw materials used improves the economics of the overall process, thereby greatly reducing raw material costs. Utilizes hydrogen and carbon monoxide as the primary or only flammable material, if desired, despite the teachings in U.S. Patent No. 7,665,209 to remove carbon dioxide from off-gas. Then, the concentration of carbon dioxide in the generated combustion gas increases.

  U.S. Pat. No. 3,438,732 discloses that tail gas from a manufacturing process is treated to remove hydrogen, carbon monoxide and water, and then the process is preferably performed using carbon black. Disclosed is a process for producing carbon black that is recycled as a spray gas for the feedstock. There, the inert gas resulting from tail gas consists essentially of nitrogen and carbon dioxide. This can increase the carbon black yield relative to the carbon black feedstock material.

  None of the above prior art documents address the problem of controlling porosity, in particular, reducing the porosity of the resulting carbon black. In some of the aforementioned prior art documents, the only product parameter disclosed as being affected by the process regime is the effect of combustion stoichiometry on the particle size and particle size distribution of the resulting carbon black.

  Accordingly, an object of the present invention is to provide a process for producing carbon black which is suitable for controlling the porosity of the obtained carbon black, and particularly suitable for reducing the porosity of the carbon black.

It is a further object of the invention to thereby simultaneously reduce the environmental impact of the carbon black production process. The reactor off gas (off gas) NO _X, environmental concentrations of harmful gases such as SO _X or CO ₂ in, if it is possible to reduce, is particularly beneficial.

[Summary of the Invention]

These subjects have been achieved by a furnace process for the production of carbon black, including:
- O ₂ containing gas stream, a fuel stream and comprising a combustible material, feeding optionally, one or more additional gas stream into the furnace reactor;
- the Tamee supplying hot flue gas (flue gas) flow in the combustion process, the combustible material, step subjected to combustion; wherein the O ₂ containing gas stream, containing the flammable material, A fuel stream and, if desired, one or more additional gas streams are provided to the combustion process in an amount that provides a k-factor of less than 1.2, wherein the k-factor is provided to the combustion process. It is defined as the ratio of O ₂ theoretically required for stoichiometric combustion of all combustible materials in the combustion process to the total O ₂ .
Contacting the carbon black feedstock with a stream of hot flue gas in a reaction step for forming carbon black;
-Stopping the carbon black formation reaction in the stopping step;
Here, the combined flow supplied to the combustion process is less than 20.5% by volume of O ₂ , based on the total volume of the gaseous components, excluding the combustible components supplied to the combustion process; Contains less than 5% by volume carbon dioxide, and / or
An inert gas stream containing at most 16% by volume of the sum of the components selected from the oxygen-containing compounds is fed to at least one reaction step and a stop step.

By using the process of the present invention, furnace black may be manufactured to have a statistical thickness specific surface area of 350 meters ² / g from 130m ² / g (STSA surface area), where
If the statistical thickness specific surface area (STSA surface area) is in the range from 130 m ² / g to 150 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.1 And
- statistical thickness ratio surface area (STSA surface area) is, in the case of from greater 180 m ² / g than 150 meters ² / g, for statistical thickness ratio surface area (STSA surface area), the ratio of BET surface area, less than 1.2 Yes,
If the statistical thickness specific surface area (STSA surface area) is greater than 180 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.3; and
The statistical thickness specific surface area (STSA surface area) and BET surface area are measured according to ASTM D 6556.

Preferably, furnace black of the present invention, has a statistical thickness specific surface area of 350m ² / g (STSA surface area) from 140 m ² / g. here,
The ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.1 when the statistical thickness specific surface area (STSA surface area) is in the range from 140 m ² / g to 150 m ² / g; , Preferably less than 1.09,
- statistical thickness ratio surface area (STSA surface area) is, in the case of from greater 180 m ² / g than 150 meters ² / g, for statistical thickness ratio surface area (STSA surface area), the ratio of BET surface area is less than 1.2, Preferably less than 1.15,
If the statistical thickness specific surface area (STSA surface area) is greater than 180 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.3, preferably 1. It is less than 25.

Furthermore, the invention relates to an apparatus for operating a preferred embodiment of the process according to the invention, comprising:
a) include the following, furnace reactor - first reaction zone to produce a hot flue gas (flue gas) stream, and, in a first reaction zone, in order to supply the O ₂ containing gas stream Providing at least one line in flow connection with the first reaction zone and at least one line, and a fuel flow comprising a combustible material to the first reaction zone. At least one line in flow connection (in flow connection) with one reaction zone;
For contacting a hot flue gas stream with a carbon black feedstock downstream of the first reaction zone and in flow connection therewith (in flow connection); A second reaction zone and at least one line in flow connection (in flow connection) with the second reaction zone for supplying a carbon black feedstock to the second reaction zone; And
-Including means for quenching the carbon black forming reaction downstream of and in flow connection with the second reaction zone (in flow connection), for stopping the carbon black forming reaction; A third reaction zone; and b) a supply unit for an inert gas;
c) at least one line connecting the inert gas supply unit and either the reactor or a supply line for supplying material to the reactor in order to supply the reactor with an inert gas stream; ;
Here, the inert gas supply unit (9) is selected from a supply line connecting the external inert gas generation equipment and the device, the storage unit (9) or the air separation unit (9).

Detailed description of the invention

  The present inventors have recognized that the porosity of the furnace black can be controlled by modifying known furnace processes.

In the method of the present invention, the O ₂ containing gas stream, a fuel stream comprising combustible material is fed to the furnace reactor of the combustion process. The fuel stream is subjected to combustion in a combustion process to provide a hot flue gas stream. The combustion process takes place in a first reaction zone of a furnace reactor, sometimes called a pre-combustion chamber. The resulting hot flue gas stream is preferably 1000-2600 ° C., preferably 1200-2,500 ° C., more preferably 1300-2400 ° C., and most preferably 1,2 ° C. It has a temperature in the range of 500-2100C. The geometry of the pre-combustion chamber is not critical to the process of the present invention and depends on the type of reactor used in the process. The geometry can be varied as known to those skilled in the art to adjust the process to other requirements not essential to the invention. Examples of suitable combustors are described in EP2361954A1, US Pat. No. 6,391,274B1, DE1952565A1, US Pat. No. 8,735,488B2.

  Because of the high temperature of the generated flue gas, the pre-combustion chamber is reinforced with a suitable refractory material that can be easily selected by one skilled in the art depending on the temperature obtained during the process of the present invention. (Lined). Alternatively, the walls of the reactor can be cooled by a gas or liquid stream.

  Any material that is flammable can be used as the fuel stream according to the present invention. Preferably, the fuel stream comprises liquid and / or gaseous hydrocarbons, and the fuel stream comprises at least 50% by weight, more preferably at least 70% by weight, even more preferably at least 90% by weight, and most preferably Preferably, it contains at least 95% by weight of hydrocarbons. The use of natural gas is particularly preferred. If desired, the fuel stream can be preheated before entering the combustion zone.

As O ₂ containing gas stream, containing oxygen gas can be any gas stream. Air, oxygen-reduced or oxygen-enriched air is particularly suitable.

According to the present invention, O ₂ containing gas stream, a fuel stream and, optionally, an inert gas stream in an amount to provide less than 1.2 k-factor, is supplied to the combustion process in the furnace reactor . Here, the k-factor is defined as the ratio of O ₂ theoretically required for the stoichiometric combustion of all combustible materials in the fuel stream to the total O ₂ amount in the combustion process. . Preferably, the k-fighter is between 0.15 and 1.2, more preferably between 0.3 and 1.15, even more preferably between 0.75 and 1.15, particularly preferably between 0.85 and 1.1. And most preferably from 0.95 to 1.05. The contents and the type of combustible materials in the feed stream, and, O ₂ content of the flow to the reactor and, from their respective flow rates, one skilled in the art, the K-factor, easily, that can be calculated to understand.

The upper limit for the O ₂ content of the integrated stream fed to the combustion process is 20, 19.5, 19, 18 based on the total volume of gaseous components, excluding flammable components fed to the combustion process. 0.5, 18, 17.5, 17, 16.5, 16, 15.5, 15, 14.5, 14, 13.5 or 13% by volume. Is supplied to the combustion process, the lower limit value of the O ₂ content of the integrated flow excluding combustible components supplied to the combustion process, based on the total volume of the gaseous components, 1.0, 1.5, It can be 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, or 6% by volume. Is supplied to the combustion process, the upper limit of the CO ₂ content of the integrated flow, based on the total volume of the gaseous components excluding the combustible components supplied to the combustion process, less than 3, less than 2.5, 2 It can be less than 0.0, less than 1.5, less than 1.0, and less than 0.5% by volume.

  In the process according to the invention, the hot flue gas generated in the combustion step, ie the pre-combustion chamber, is brought into contact with the carbon black feed in a reaction step. In the reaction step, pyrolysis of the carbon black feedstock occurs and carbon black is formed. According to the invention, the cross section of the furnace reactor in flow direction behind the first reaction zone or pre-combustion chamber can be reduced or enlarged. The part of the reactor that is in flow direction behind the first reaction zone or pre-combustion chamber can form a second reaction zone where mainly the carbon black forming reaction takes place. The second reaction zone generally extends from where the first carbon black feedstock material enters the reactor to where the cessation of the carbon black formation reaction begins, as described in more detail below. The actual length and geometry of the second reaction zone will vary widely, depending on the type of reactor used and the specific conditions of the process for the carbon black actually produced. be able to.

  Generally, the carbon black feedstock material can be supplied to the reaction step by any suitable means. The carbon black feedstock material can be injected radially, for example, using radial lances, or one or more axial lances can be added to the second reaction zone. Can be used to inject axially. Any suitable carbon-containing material known to those skilled in the art as suitable for carbon black production can be used. Suitable carbon black feedstocks can be selected from liquid and gaseous hydrocarbons such as coal tar oil, steam cracker oils, cat cracker oils, natural oils or natural gas. It is particularly useful to use the liquid hydrocarbon-containing oils described above as carbon black feedstock materials.

  In the stopping step, the carbon black forming reaction is stopped. Shutdown can be performed in a third reaction zone downstream of the second reaction zone, also referred to as a quench zone. Termination of the carbon black forming reaction can be achieved by any means known to those skilled in the art. Thereby, not only the reactor off-gas (off-gas) but also the formed carbon black is cooled, and the carbon black formation reaction is stopped. Cooling can be achieved by direct or indirect heat exchange, for example, by using cooled reactor walls, quench boilers, or quenching. Preferably, quenching can be achieved by injecting a suitable quench liquid. According to the invention, it is also preferred that the cross section of the furnace reactor in the quenching zone is increased compared to the second reaction zone. The quenched liquid can be injected at various points in the furnace reactor, depending on the desired properties of the carbon black to be produced. The quench liquid can be injected axially and / or radially at different locations in the reactor. Of course, it is also possible to use any combination of different possible injection locations for the quenching liquid. Preferably, water is used as the quench liquid.

  A particular advantage of the present invention is that the process is no longer limited to using a quench location near the second reaction zone to produce low porosity carbon black. Thus, as is well known to those skilled in the art, produce a wider range of carbon black with the desired properties, but still low porosity, as porosity is no longer determined solely by the quench position. be able to. This has been described above in the introduction.

After passing through the quench zone of the reactor, the reaction mixture containing the carbon black formed, as well as the off-gas of the reactor, is preferably introduced into a heat exchanger. This allows the reaction mixture to cool, allowing further processing, such as separating the formed carbon black from the reactor off-gas. Further, in the heat exchanger, it is used to burn the fuel flow, O ₂ containing gas, in order to increase the overall energy efficiency of the process may be pre-heated. For further processing, one or more heat exchangers can be used to reduce the temperature of the reaction mixture to an appropriate level.

  Subsequently, the reaction mixture is subjected to a gas / solid separation operation in order to separate the carbon black from the reactor off-gas. Typically, a filter is used to separate the carbon black from the reactor off-gas. Further processing steps of the obtained carbon black and the reactor off-gas may follow.

An object of the present invention, as described above, k-Factor, was adjusted to less than 1.2, and, while limiting the amount of CO ₂ fed to the reactor, the inert gas concentration in the reactor Achieved by comparing to an increasing, standard furnace process.

This provides less than 20.5% by volume of O ₂ and less than 3.5% by volume of carbon dioxide based on the total volume of the gaseous components excluding the combustible components supplied to the combustion process. This is achieved according to the invention by providing an integrated flow. Alternatively, an inert gas stream comprising up to 16% by volume of the sum of the components selected from the oxygen-containing compounds is supplied to at least one carbon black forming step and a stopping step. As will be appreciated by those skilled in the art, both methods can be combined.

As the inert gas, any gas that does not interfere with the carbon black production process under reaction conditions widely performed in the reactor can be used. Thus, the inert gas stream should contain up to 16% by volume of the total amount of components selected from oxygen-containing compounds. Suitable upper limits for the amount of oxygen containing compound are up to 15% by volume, up to 14% by volume, up to 13% by volume, up to 12% by volume, up to 11% by volume, up to 10% by volume, up to 9% by volume, up to 8% by volume , Up to 7%, up to 6%, up to 5%, up to 4% or up to 3% by volume. The lower limit for the amount of oxygen containing compound can be 0.01%, 0.1%, 0.3%, 0.5%, 1% or 2% by volume. In particular, the total amount of any type of oxidizing compound, such as nitrogen oxides, as well as molecular oxygen, water, carbon monoxide, and carbon dioxide, must be controlled below a specified value. Suitable inert gases are at least, N ₂ containing gas containing 84 vol% of N _2; may be selected from and ammonia. The N ₂ -containing gas is particularly preferably used as an inert gas. Suitable N ₂ containing gas is 84-99.9999% by volume of N _2, more preferably 90-99.99% by volume of N _2, even more preferably from 92 to -99.99% by volume N ₂ , most preferably containing 95-99% by volume of N _2.

Since the reactor off-gas contains significant amounts of water, CO and CO ₂ , the reactor off-gas is such that all of these components are below the levels described above. Can be used only as an inert gas. This is not economically attractive in most cases. Therefore, it is preferred that the inert gas does not come from the reactor off-gas.

According to the present invention, the inert gas can be supplied directly or indirectly to the combustion step, the reaction step, the shutdown step, or any combination thereof. For example, in the heat exchanger, prior to preheating the O ₂ containing gas stream, or, already in one of the preheated oxygen-containing gas stream, to be mixed with an inert gas and an oxygen-containing gas stream It is possible. Alternatively, the inert gas stream can be supplied directly to the combustion process. For example, it is possible to introduce an inert gas into the reaction process by using it as a spray gas for the carbon black feedstock. Of course, any combination thereof can also be used. In particular, prior to the preheating, it is preferable to mix the inert gas flow and O ₂ containing gas stream.

Inert gas stream containing O _2, and, in the combustion process, when it is directly or indirectly fed, in accordance with the present invention, when calculating the k- factor, one skilled in the art, by the inert gas stream It is introduced into the combustion process, to understand that it must consider the O _2. Therefore, directly or indirectly, supplied to the first reaction zone, containing O _2, inert gas stream, for generating a hot flue gas of the present invention (flue gas), O ₂ It can be at least part of a contained gas stream.

In the reactor containing all of the above embodiments, instead of supplying the inert gas stream, or the same in combination, as compared to the air, it has a reduced content of oxygen-containing compounds, O ₂ containing gas stream Can be supplied to the combustion process. In this embodiment, O ₂ containing gas stream fed to the combustion process, involving a total amount of the selected component from the oxygen-containing compounds of less than 20.5% by volume. In particular, as with molecular oxygen, water, carbon monoxide, and carbon dioxide, it is necessary to control the total amount of any type of oxidizing compound, such as nitrogen oxide, to a specified level or less. Of course, O ₂ containing gas stream to support combustion of the fuel flow, and, according to the present invention, in order to obtain a k- factor, it is necessary to contain sufficient oxygen. Further, when the content of oxygen gas is too low, within the scope of the present invention, k-factor for adjusting the, then, because high flow rates of O ₂ containing gas stream is required, the process is economically Not a target. Thus, for this embodiment, the content of O ₂ in the O ₂ containing gas is preferably from 1 to 20.5% by volume. Suitable upper limits for the content of O ₂ in the O ₂ -containing gas are 20, 19.5, 19, 18.5, 18, 17.5, 17, 16.5, 16, 15.5, 15, 14.5, 14, 13.5 or 13% by volume. The lower limit of the O ₂ content in the O ₂ -containing gas is 1.0, 1.5, ₂ , 2.5, 3, 3.5, 4, 4.5, 5, 5.5 or 6% by volume. It can be.

The k-factor close to the stoichiometric combustion of the fuel stream is significantly higher than the resulting hot flue gas temperature, compared to the oxygen-enriched combustion scheme, with a lower k-factor. Lead. First reaction zone, i.e., the pre-combustion chamber, directly or indirectly, by supplying the inert gas, and / or has a reduced content of oxygen-containing compounds, using an O ₂ containing gas stream This has the added advantage that the temperature of the hot flue gas is thereby reduced to some extent in order to limit the thermal stress on the lining of the refractory material in the reactor. Have.

  The inert gas is preferably nitrogen. Nitrogen can be provided to the process of the present invention from any available source. It is also possible to use low-purity nitrogen gas as long as the total amount of components selected from oxygen-containing compounds is less than 16% by volume. Thus, it is also possible to use nitrogen-enriched process gases from carbon black processes or other industrial processes, as long as the oxygen-containing compound is purified to meet the above limitations. However, as described above, it is preferable not to use an inert gas derived from the reactor off-gas of the carbon black production process. A flask bundle of inert gas or an inert gas storage tank, as described above, is connected via a line to the appropriate feed point at the appropriate location in the furnace reactor used in the process of the present invention. Can be connected. Alternatively, an inert gas, preferably nitrogen, can be supplied to the process according to the invention via a pipeline from an external inert gas production facility.

Preferably, the nitrogen is produced by separating nitrogen from air using any type of air separation process known to those skilled in the art. Suitable readily available and economical processes suitable for producing nitrogen of the required purity include pressure swing adsorption processes and membrane separation processes. A pressure swing adsorption process is particularly preferred. Thereby, pressurized air is supplied to the pressure swing adsorption unit, where oxygen is adsorbed on the carbon molecular sieve at a high pressure in the range of 8-12, preferably about 10 bar. Thus, suitable purity nitrogen (92 to 99.99% by volume of N _2, preferably N ₂ for 95 to 99 vol%) is obtained. This nitrogen can then be used as an inert gas in the method of the present invention. The adsorbed oxygen is desorbed from the carbon molecular sieve at ambient pressure (about 1 bar) or under reduced pressure. The oxygen thus obtained can be used in the next possible step in the production of carbon black. Alternatively, oxygen can be used in processes other than the carbon black manufacturing process.

  Accordingly, the present invention also relates to a device, wherein the inert gas supply unit replaces the external inert gas production facility with the device, storage unit or air separation unit, preferably air, nitrogen-free gas. A supply line connected to a pressure swing adsorption unit or a membrane separation unit for separating an active gas stream and an oxygen-enriched gas stream, and the inert gas supply unit is a furnace reaction. The reactor is connected to either an oxygen-containing gas, a fuel stream, a line for supplying a carbon black feed or a quench material to supply an inert gas to the reactor.

According to a preferred embodiment, the apparatus comprises a hot reaction mixture leaving the furnace reactor, the O ₂ containing stream, for preheating, at least one heat exchanger unit. Inert gas supply unit, preferably, the pressure swing adsorption unit or a membrane separation unit, before entering the heat exchanger, via a supply line of the inert gas, is connected to the supply line of the O ₂ containing stream.

  Using the process of the present invention, furnace black can be produced that has low porosity despite its large external surface area (STSA surface area). Statistical thickness specific surface area (STSA surface area) is a measure of the outer surface of carbon black that correlates with particle size. The smaller the carbon black particles, the greater the external surface area. BET surface area is a measure of external and internal surface area. As a result, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is an indicator of the porosity of carbon black. If the ratio of BET to statistical thickness specific surface area (STSA surface area) is about 1, then carbon black has no porosity. In general, carbon blacks, especially with a small particle size and thus a large external surface area or STSA area, also have a high BET surface area to statistical thickness specific surface area (STSA surface area) Significantly deviates from "1", which indicates having porosity. It is therefore a surprising result that the process of the present invention results in a carbon black having a large external surface area, but still having a low porosity.

Furnace black according to the present invention has a mould of from 130 m ² / g to 450 m ² / g, preferably from 140 m ² / g to 300 m ² / g, more preferably from 150 m ² / g to 280 m ² / g, most preferably. It has a statistical thickness specific surface area (STSA surface area) of 160 m ² / g to 250 m ² / g.

For the furnace black of the present invention, if the statistical thickness specific surface area (STSA surface area) is in the range of 130 m ² / g to 150 m ² / g or 140 m ² / g to 150 m ² / g, the statistical thickness The ratio of the BET surface area to the specific surface area (STSA surface area) is less than 1.1.

When the statistical thickness specific surface area (STSA surface area) is in the range of 150 m ² / g to 180 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.2. It is. When the statistical thickness specific surface area (STSA surface area) is larger than 180 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.3. Preferably, when the statistical thickness specific surface area (STSA surface area) is in the range of 130 m ² / g to 150 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is 1 BET surface area to statistical thickness specific surface area (STSA surface area) when the statistical thickness specific surface area (STSA surface area) is less than 0.09 and the statistical thickness specific surface area (STSA surface area) is in the range of 150 m ² / g to 180 m ² / g. Is less than 1.15. When the statistical thickness specific surface area (STSA surface area) is larger than 180 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.25.

  Further, the furnace black according to the present invention can have an OAN value of 100-150 ml / 100 g.

Particularly preferred furnace blacks according to the invention exhibit an STSA surface area of at least 130 m ² / g. here,
If the statistical thickness specific surface area (STSA surface area) is in the range from 130 m ² / g to 150 m ² / g or 140 m ² / g to 150 m ² / g, relative to the statistical thickness specific surface area (STSA surface area) , BET surface area ratio is less than 1.09.
- statistical thickness ratio surface area (STSA surface area) is, in the case of from greater 180 m ² / g than 150 meters ² / g, for statistical thickness ratio surface area (STSA surface area), the ratio of BET surface area is less than 1.15 is there.
If the statistical thickness specific surface area (STSA surface area) is greater than 180 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.25.
The OAN value is in the range of 100-150 ml / 100 g.

  Further, the furnace black according to the present invention can have an iodine value of 125 or more.

  As shown throughout this application, the properties of carbon black are measured as follows.

BET surface area and STSA surface area according to ASTM D-6556 (2014).

OAN according to ASTM D-2414 (2013).

Iodine value according to ASTM D-1510 (2013).

In addition, the process according to the present invention not only controls, and in particular allows for a reduction in the porosity of the carbon black produced by the process, but also the off-gas (off- It is an even more surprising result to allow a reduction in the concentration of the compound in the gas. As shown in the experimental data, in particular, it is possible to reduce the concentration of the NO _X and / or SO _x in the off gas (off-gas).

A further advantage of the process according to the invention is that the amount of carbon black formed is significantly increased for the feedstock used compared to the furnace process, where the concentration of inert gas in the reactor is not increased. Is what you can do. Thus, the process of the present invention is not only suitable for controlling, i.e., reducing, the porosity of furnace black, but also in combination or alternatively, is indicated by an increased carbon black yield. It also leads to an improvement in overall economic efficiency. This also improves the overall carbon dioxide balance of the process according to the invention. Accordingly, the present invention also provides a process for reducing the emissions of CO ₂ from increasing and the process of the carbon black yield. As a result, a more economical and environmentally acceptable process for producing carbon black is provided.

  The present invention will be described in more detail with reference to the drawings and embodiments.

FIG. 1 shows a schematic diagram of the process and apparatus according to the invention.

As shown in FIG. 1, the process according to the invention is carried out in a furnace reactor 1 having three different reaction zones in the inflow direction. Up to the first reaction zone 2, also called the combustion zone, a fuel stream containing combustible material is supplied via line 5 and an O ₂ -containing gas stream is supplied via line 6. Is done. The fuel stream is subjected to combustion in a first reaction zone 2 to provide hot flue gas. As shown in FIG. 1, the diameter of the furnace reactor is reduced so as to form a second reaction zone 3 where the carbon black feed is contacted with hot flue gas. The carbon black feed is supplied via line 7 to the second reaction zone 3 in the narrow part of the furnace reactor. This can be achieved by having a plurality of radially arranged inlets, such as oil lances (not shown). Alternatively or additionally, carbon black feedstock material can also be injected into the second reaction zone 3 via an axial lance. In the second reaction zone 3, carbon black is formed by decomposition of the carbon black feedstock material. The resulting pyrolysis reaction mixture enters a third reaction zone 4, also called a quench zone. The quenched material can be supplied to a quenched region via a quenched material line 8 to a plurality of locations. In quench zone 4, the reaction mixture is essentially cooled to a temperature low enough to stop the carbon black formation reaction. At this point, the reaction mixture is in a state where the carbon black particles are dispersed in the continuous gas phase of the reaction gas. After exiting the furnace reactor, the reaction mixture is directed to one or more (FIG. 1) heat exchange units 11 to further reduce the temperature of the reaction mixture. Thereby, the heat removed from the reaction mixture is used to preheat the O ₂ -containing gas stream before entering the first reaction zone 2. The cold O ₂ -containing gas stream is supplied to the heat exchange unit 11 via line 13 and the preheated, oxygen-containing gas stream is supplied to the first reaction zone 2 via line 6. .

FIG. 1 shows possible positions for supplying a stream of inert gas to the reactor. One suitable position supplies before entering the heat exchanger 11, the storage or production unit 9 of inert gas, via line 10, line 13 of the cold O ₂ containing gas, an inert gas That is. As mentioned above, unit 9 is preferably a pressure swing adsorption unit. Alternatively, the inert gas is supplied via line 10 to line 6 which supplies a preheated O ₂ -containing gas stream to first reaction zone 2. It is also possible to supply an inert gas stream to the first reaction zone 2 of the reactor 1 directly via the line 10. Most preferably, the inert gas stream is fed via line 10 to a line 13 of cold, O ₂ -containing gas before entering the heat exchanger 11.

  The cooled, solid / gaseous reaction mixture exiting the heat exchange unit 11 is directed to a separation unit 14, where carbon black particles are recovered from the reaction mixture. Separation unit 14 is preferably a filter unit. The solid carbon black is further directed to a discharge unit 15 for further processing and storage. And also, before the separated gas phase is released to the environment, it is led to further processing units for cooling and gas treatment.

In the examples, as shown, the apparatus shown in FIG. 1 was used. Here, the carbon black feedstock is injected into the second reaction zone 3 via an oil lance that is 4 radially oriented. As the inert gas, nitrogen is used, prior to entering the heat exchanger 11, line 13 of the cold O ₂ containing gas directly supplied. Table 1 shows the process parameters and characteristics of the obtained carbon black.

^One tail gas is extracted from the production line and filtered to remove carbon black. Thereafter, the tail gas is cooled to + 4 ° C. to freeze the water. Then, in order to completely remove water, phosphorus pentoxide is passed. The tail gas composition without water is analyzed on an Inficon 3000 Micro GC Gas Analyzer to obtain the molar fraction of CO. The Inficon 3000 Micro GC Gas Analyzer is frequently calibrated with a designated reference gas.

( ² ) The sulfur flow rate in tail gas is calculated via mass balance. The carbon black sulfur flow rate is subtracted from the feedstock sulfur flow rate. The difference is the sulfur flow in the tail gas. The sulfur content of the feedstock and carbon black is analyzed using "Vario EL Cube" CHNS elemental analysis from "Elemental Analysis System". The sulfur flow rates of the feedstock and carbon black are calculated taking into account the mass flow rates of the feedstock and carbon black and the sulfur concentrations in the feedstock and carbon black.

Claims (16)

Furnace black having a statistical thickness specific surface area (STSA surface area) of 130 m ² / g to 350 m ² / g, wherein:
The ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.1 when the statistical thickness specific surface area (STSA surface area) is in the range from 130 m ² / g to 150 m ² / g; And
- statistical thickness ratio surface area (STSA surface area) is, in the case of from greater 180 m ² / g than 150 meters ² / g, for statistical thickness ratio surface area (STSA surface area), the ratio of BET surface area, less than 1.2 Yes,
If the statistical thickness specific surface area (STSA surface area) is greater than 180 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.3, and
The statistical thickness specific surface area (STSA surface area) and BET surface area are measured according to ASTM D 6556, furnace black. A statistical thickness specific surface area (STSA surface area) of 140 m ² / g to 300 m ² / g, preferably 150 m ² / g to 280 m ² / g, more preferably 160 m ² / g to 250 m ² / g Have. The furnace black of claim 1. Furnace black according to any one of the preceding claims, wherein:
If the statistical thickness specific surface area (STSA surface area) is in the range from 130 m ² / g to 150 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is 1.09 Less than,
- statistical thickness ratio surface area (STSA surface area) is, in the case of from greater 180 m ² / g than 150 meters ² / g, for statistical thickness ratio surface area (STSA surface area), the ratio of BET surface area, less than 1.15 Yes,
Furnace black, wherein the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.25 when the statistical thickness specific surface area (STSA surface area) is greater than 180 m ² / g. According to any one of the preceding claims, a furnace black having a statistical thickness specific surface area of 350 meters ² / g from 140m ² / g (STSA surface area), where
The ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.1 when the statistical thickness specific surface area (STSA surface area) is in the range from 140 m ² / g to 150 m ² / g; And preferably less than 1.09,
- statistical thickness ratio surface area (STSA surface area) is, in the case of from greater 180 m ² / g than 150 meters ² / g, for statistical thickness ratio surface area (STSA surface area), the ratio of BET surface area, less than 1.2 And preferably less than 1.15;
If the statistical thickness specific surface area (STSA surface area) is greater than 180 m ² / g, the ratio of the BET surface area to the statistical thickness specific surface area (STSA surface area) is less than 1.3, preferably , Furnace black which is less than 1.25.   A method according to any one of the preceding claims, wherein the OAN value measured according to ASTM D2414 is 20-200 ml / 100 g, preferably 30-170 ml / 100 g, more preferably 100-170 ml / 100 g. Furnace black as described. A furnace process for the production of carbon black, comprising:
- O ₂ containing gas stream (O _{2 -containing} gas stream), a fuel stream containing the combustible material (fuel stream comprising combustible material), and, optionally, one or more additional gas flow, furnace reactor ( furnishing to a reactor (furnace reactor);
- To provide the hot flue gases (flue gas) flow in the combustion process, the combustible material, the process is subjected to combustion; wherein the O ₂ containing gas stream, a fuel stream containing combustible material, And, optionally, one or more additional gas streams are provided to the combustion process in an amount that provides a k-factor of less than 1.2, wherein the k-factor is the total O ₂ supplied to the combustion process. It is defined as the ratio of the amount of O ₂ theoretically required for stoichiometric combustion of all combustible materials in the combustion process to the amount.
Contacting the carbon black feedstock with a stream of hot flue gas in a reaction step for forming carbon black;
-Stopping the carbon black formation reaction in the stopping step;
Here, the combined streams supplied to the combustion process are based on the total amount of gaseous components excluding the combustible components supplied to the combustion process, with less than 20.5% by volume of O ₂ and Contains less than 3.5% by volume of carbon dioxide; and / or
A furnace process wherein an inert gas stream comprising up to 16% by volume of the total amount of components selected from oxygen-containing compounds is supplied to at least one reaction step and a stop step.   the k-factor is between 0.15 and 1.2, preferably between 0.3 and 1.15, more preferably between 0.75 and 1.15, even more preferably between 0.85 and 1.1; 7. The process of claim 6, wherein the ratio is from .95 to 1.05. 8. The process of claim 6 or 7, wherein based on the total amount of gaseous components excluding flammable components provided to the combustion step, combined streams provided to the combustion step are: 1.0 to 20.0, preferably 2.5 to 19.5, more preferably 5.0 to 19.0% by volume of O ₂ and / or less than 2.0, preferably less than 1.0, A process containing preferably less than 0.5% by volume of carbon dioxide.   9. The process according to any one of claims 6 to 8, wherein the oxygen-containing gas stream is air, optionally oxygen-enriched or oxygen-free air.   10. The process according to any one of claims 6 to 9, wherein the fuel stream comprises natural gas. 11. The process according to any one of claims 6 to 10, wherein the inert gas stream comprising the total amount of components, selected from up to 16% by volume of oxygen-containing compounds, comprises: combustion process, the reaction step, stopping step, O ₂ containing gas stream, fuel flow, or fed to any feed line for the carbon black feedstock, or quenching material (quench material) is, in the stopping step, using If so, it is supplied to the quenched material or combination thereof. Preferably, furnace reactor further comprises a preheater for the O ₂ containing gas stream, and the inert gas stream, before entering the heat exchanger, supplied to the supply line of the O ₂ containing gas stream Is a process. A process according to any one of claims 6 to 11, wherein the inert gas is selected from N ₂ containing gas and ammonia containing N ₂ for at least 84 vol%, preferably, not active gas flow, 84-99.9999% by volume of N _2, more preferably 90-99.99% by volume of N _2, even more preferably 92-99.99% by volume of N _2, and most preferably 95- containing 99% by volume of N _2, the process.   13. An air separation unit, preferably further comprising separating air in a pressure swing adsorption unit or a membrane separation unit into a nitrogen-containing gas stream and an oxygen-enriched gas stream. The process of claim 1 wherein the nitrogen-containing gas stream is used as an inert gas stream and the oxygen-enriched gas stream optionally comprises a process for producing carbon black. Process used in An apparatus for operating the process according to any one of claims 6 to 13,
a) Furnace reactor (1) including:
- a first reaction zone (2) and O ₂ containing gas stream to produce a hot flue gas (flue gas) stream, to be supplied to the first reaction zone (2), the first reaction zone ( A first reaction zone for supplying a fuel flow comprising a combustible material to at least one line (6) in flow connection with 2) and a first reaction zone (2); At least one line (5), which is in flow connection with (2).
Downstream of the first reaction zone (2), a second reaction zone for contacting an inflow-connected carbon black feedstock with a hot flue gas stream; And (3) at least one line (in flow connection) with the second reaction zone (3) for supplying a carbon black feedstock to the second reaction zone (3). 7); and- inflow connection (in flow connection) carbon black downstream of the second reaction zone (3), including means (8) for quenching the carbon black production reaction. A third reaction zone (4) for stopping the production reaction; and
b) an inert gas supply unit (9); and c) an inert gas supply unit (9) and a reactor (1) or feed the reactor to supply the inert gas stream to the reactor. At least one line (10) connecting with any supply line (5, 6, 7, 8) for
Here, the inert gas supply unit (9) is selected from a supply line connecting the external inert gas production equipment with the device, the storage unit (9) or the air separation unit (9).
An apparatus, including:   At least one supply line (in flow connection) with the third reaction zone for supplying quench material to the oxygen-containing gas stream and / or the third reaction zone; Apparatus according to claim 14, further comprising a preheater (11) for 8). 16. The device according to claim 14 or 15, wherein the air separation unit (9) is preferably a pressure swing adsorption unit or a membrane separation unit (9) and the inert gas supply unit (9) is A device connected via at least one line (10) for supplying an inert gas stream to:
- before entering the preheater (11), O ₂ containing gas flow line for supplying (13);
- preheater (11) downstream, O ₂ containing gas flow line for supplying (6);
-A line (5) for supplying a fuel stream;
A line (7) for supplying a carbon black feedstock;
The means for quenching the carbon black production reaction is a line for supplying quenched material to a line for supplying quenched material (8);
A first reaction zone (2);
A second reaction zone (3);
A third reaction zone (4); or a combination thereof,
Preferably, a line (13) for supplying a stream of oxygen-containing gas before entering said preheater.